Optical lens assembly for image taking

ABSTRACT

An optical lens assembly for image taking includes a first lens element, a second lens element, a third lens element and a fourth lens element. The first lens element with positive refractive power includes a convex object-side surface at a paraxial region. The second lens element with negative refractive power includes a concave object-side surface at a paraxial region. The third lens element with refractive power includes a concave object-side surface at a paraxial region and a convex image-side surface at a paraxial region. The fourth lens element made of plastic with negative refractive power includes a concave object-side surface at a paraxial region and an image-side surface. At least one of the object-side surface and the image-side surface of the fourth lens element is aspheric, and the image-side surface of the fourth lens element is concave at a paraxial region and convex at a peripheral region.

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims priority under 35 U.S.C. §119(a)on Patent Application No(s). 101125413 filed in Taiwan, R.O.C. on Jul.13, 2012, the entire contents of which are hereby incorporated byreference.

BACKGROUND OF THE INVENTION

1. Technical Field

The present disclosure relates to an optical lens assembly for imagetaking, and more particularly, to an optical lens assembly for imagetaking having multiple lens elements.

2. Related Art

In recent years, with the rise of portable electronic device withphotographing capability, the demand for compact imaging lens assemblyhas been increasing. The photo-sensing device of an ordinaryphotographing camera is none other than a CCD (charge coupled device) ora CMOS (complementary metal-oxide semiconductor sensor). Furthermore, asadvances in semiconductor manufacturing technology have allowed thepixel size of sensors to be reduced, and the resolution of the compactimaging lens assembly has gradually increased, there is an increasingdemand for the compact imaging lens assembly featuring better imagequality. A three-lens structure is commonly adopted in a conventionalcompact photographing lens assembly of the portable electronic products.For example, in U.S. Pat. No. 7,145,736, a photographing lens assemblyincludes, in order from an object side to an image side, a first lenselement with positive refractive power, a second lens element withnegative refractive power and a third lens element with positiverefractive power. With the advances of semiconductor manufacturingtechnology and the development of compact electronic devices, imagequality of the compact imaging lens assembly is highly required but theconventional three-lens photographing lens assembly may not satisfy thedemand for better image quality.

Moreover, the specification of U.S. Pat. No. 7,969,664 discloses afour-lens assembly. Although with the addition of a fourth lens element,the image quality is superior to the conventional three-lensphotographing lens assembly. However, since the third lens element withpositive refractive power is favorable for reducing the total tracklength of this four-lens assembly, the image quality may not satisfy thehigh-end imaging lens assembly for having larger aberration.

SUMMARY OF THE INVENTION

According to an embodiment, an optical lens assembly for image takingcomprises, in order from an object side to an image side, a first lenselement with positive refractive power comprising a convex object-sidesurface at a paraxial region and an image-side surface, a second lenselement with negative refractive power comprising a concave object-sidesurface at a paraxial region and an image-side surface, a third lenselement with refractive power comprising a concave object-side surfaceat a paraxial region and a convex image-side surface at a paraxialregion, and a fourth lens element made of plastic with negativerefractive power comprising a concave object-side surface at a paraxialregion and a concave image-side surface at a paraxial region. Theimage-side surface of the fourth lens element is convex at a peripheralregion. At least one of the object-side surface and the image-sidesurface of the fourth lens element is aspheric.

The optical lens assembly for image taking satisfies the followingconditions:

1.45<T ₂₃ /CT ₃<3.0

−0.15<R ₁ /R ₂<0.50

0.70<Dr ₁ r ₄ /T ₂₃<1.08

wherein T₂₃ is an axial distance between the second lens element and thethird lens element; CT₃ is a central thickness of the third lenselement; R₁ is a curvature radius of the object-side surface of thefirst lens element; R₂ is a curvature radius of the image-side surfaceof the first lens element; and Dr₁r₄ is an axial distance between theobject-side surface of the first lens element and the image-side surfaceof the second lens element.

According to another embodiment, an optical lens assembly for imagetaking comprises, in order from an object side to an image side, a firstlens element with positive refractive power comprising a convexobject-side surface at a paraxial region and an image-side surface, asecond lens element with negative refractive power comprising a concaveobject-side surface at a paraxial region and an image-side surface, athird lens element with refractive power comprising a concaveobject-side surface at a paraxial region and a convex image-side surfaceat a paraxial region, and a fourth lens element made of plastic withnegative refractive power comprising a concave object-side surface at aparaxial region and a concave image-side surface at a paraxial region.The image-side surface of the fourth lens element is convex while at aperipheral region. At least one of the object-side surface and theimage-side surface of the fourth lens element is aspheric.

The optical lens assembly for image taking comprises a stop andsatisfies the following conditions:

1.50≦T ₂₃ /CT ₃<2.05

−0.33<R ₁ /R ₂<0.50

0.70<Dsr ₄ /Dr ₁ r ₄<0.90

wherein T₂₃ is an axial distance between the second lens element and thethird lens element; CT₃ is a central thickness of the third lenselement; R₁ is a curvature radius of the object-side surface of thefirst lens element; R₂ is a curvature radius of the image-side surfaceof the first lens element; Dsr₄ is an axial distance between the stopand the image-side surface of the second lens element; and Dr₁r₄ is anaxial distance between the object-side surface of the first lens elementand the image-side surface of the second lens element.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thefollowing detailed description when taken in connection with theaccompanying drawings, which show, for purpose of illustrations only,and thus do not limit other possible embodiments derived from the spiritof the present disclosure, and wherein:

FIG. 1A is a schematic structural view of a first embodiment of anoptical lens assembly for image taking;

FIG. 1B, FIG. 1C, FIG. 1D are schematic views of longitudinal sphericalaberration curves, astigmatic field curves, and a distortion curve,respectively in the optical lens assembly for image taking in FIG. 1A;

FIG. 2A is a schematic structural view of a second embodiment of anoptical lens assembly for image taking;

FIG. 2B, FIG. 2C, FIG. 2D are schematic views of longitudinal sphericalaberration curves, astigmatic field curves, and a distortion curve,respectively in the optical lens assembly for image taking in FIG. 2A;

FIG. 3A is a schematic structural view of a third embodiment of anoptical lens assembly for image taking;

FIG. 3B, FIG. 3C, FIG. 3D are schematic views of longitudinal sphericalaberration curves, astigmatic field curves, and a distortion curve,respectively in the optical lens assembly for image taking in FIG. 3A;

FIG. 4A is a schematic structural view of a fourth embodiment of anoptical lens assembly for image taking;

FIG. 4B, FIG. 4C, FIG. 4D are schematic views of longitudinal sphericalaberration curves, astigmatic field curves, and a distortion curve,respectively in the optical lens assembly for image taking in FIG. 4A;

FIG. 5A is a schematic structural view of a fifth embodiment of anoptical lens assembly for image taking;

FIG. 5B, FIG. 5C, FIG. 5D are schematic views of longitudinal sphericalaberration curves, astigmatic field curves, and a distortion curve,respectively in the optical lens assembly for image taking in FIG. 5A;

FIG. 6A is a schematic structural view of a sixth embodiment of anoptical lens assembly for image taking;

FIG. 6B, FIG. 6C, FIG. 6D are schematic views of longitudinal sphericalaberration curves, astigmatic field curves, and a distortion curve,respectively in the optical lens assembly for image taking in FIG. 6A;

FIG. 7A is a schematic structural view of a seventh embodiment of anoptical lens assembly for image taking;

FIG. 7B, FIG. 7C, FIG. 7D are schematic views of longitudinal sphericalaberration curves, astigmatic field curves, and a distortion curve,respectively in the optical lens assembly for image taking in FIG. 7A;

FIG. 8A is a schematic structural view of an eighth embodiment of anoptical lens assembly for image taking; and

FIG. 8B, FIG. 8C, FIG. 8D are schematic views of longitudinal sphericalaberration curves, astigmatic field curves, and a distortion curve,respectively in the optical lens assembly for image taking in FIG. 8A.

DETAILED DESCRIPTION OF THE INVENTION

The optical lens assembly for image taking of the present disclosure isdescribed to illustrate that the embodiments have similar lenscombinations, configuration relationships, and the same conditions ofthe optical lens assembly. The differences are described in detail inthe following embodiments.

The optical lens assembly for image taking comprises, from an objectside to an image side along an optical axis in sequence, a first lenselement, a stop, a second lens element, a third lens element, a fourthlens element, an IR-cut filter (infrared-cut filter) and an image planeincluding an image sensor. The stop can be an aperture stop.

The object-side surface of the first lens element with positiverefractive power may be convex at a paraxial region for providing aportion of the positive refractive power of the optical lens assemblyfor image taking, thereby shortening the total length of the opticallens assembly for image taking.

The object-side surface of the second lens element with negativerefractive power may be concave at a paraxial region for correcting theaberration resulted from the first lens element effectively as well asthe chromatism of the optical lens assembly for image taking.

The object-side surface of the third lens element is concave at aparaxial region and the image-side surface of the third lens element isconvex at a paraxial region for correcting the astigmatism of theoptical lens assembly for image taking.

The object-side surface of the fourth lens element made of plastic isconcave at a paraxial region. The image-side surface of the fourth lenselement is concave at a paraxial region and convex at a peripheralregion. Thus, the angle at which the incident light projects onto theimage sensor from off-axis field can be effectively reduced and theoff-axis aberration is further corrected. The object-side surface andthe image-side surface of the fourth lens element both are aspheric. Thefourth lens element made of plastic with negative refractive power sothe principal point of the optical lens assembly for image taking isfarther away from the image plane and the total track length of theoptical lens assembly for image taking is favorably reduced for keepingthe optical lens assembly for image taking compact.

T₂₃ is an axial distance between the second lens element and the thirdlens element and CT₃ is a central thickness of the third lens element.When the second lens element and the third lens element satisfy1.45≦T₂₃/CT₃<3.0, the heights in which the lights from the off-axisfield pass through the second lens element and the third lens elementare relatively higher so that it enables the third lens element tocorrect the field curve, the distortion and the comatic aberration forfavorably correcting the image quality. When the relation of1.50≦T₂₃/CT₃<2.05 is satisfied, it is favorable for the aforementionedcondition. In some embodiments, the following relation is satisfied:1.50≦T₂₃/CT₃<1.80.

R₁ is a curvature radius of the object-side surface of the first lenselement and R₂ is a curvature radius of the image-side surface of thefirst lens element. When the first lens element satisfies−0.33<R₁/R₂<0.50, the spherical aberration resulted from the opticallens assembly for image taking is corrected. In some embodiments, thefollowing relation is satisfied: −0.15<R₁/R₂<0.50.

Dr₁r₄ is an axial distance between the object-side surface of the firstlens element and the image-side surface of the second lens element andT₂₃ is the axial distance between the second lens element and the thirdlens element. When the relation of 0.70<Dr₁r₄/T₂₃<1.08 is satisfied, itis favorable for adjusting the aberration of the optical lens assemblyfor image taking while keeping a proper total track of length for thelens assembly.

Dr₁r₄ is the axial distance between the object-side surface of the firstlens element and the image-side surface of the second lens element andDsr₄ is an axial distance between the stop and the image-side surface ofthe second lens element. When the relation of 0.30<Dsr₄/Dr₁r₄<0.90 issatisfied, it is favorable for providing a proper field of angle andlowering the incident angle of the image plane to provide better imagequality. In some embodiments, the following relation is satisfied:0.30<Dsr₄/Dr₁r₄<0.60.

V₁ is an Abbe number of the first lens element and V₂ is an Abbe numberof the second lens element. When the first lens element and the secondlens element satisfy 1.8<V₁N₂<3.0, it is favorable for correcting thechromatism generated by the optical lens assembly for image taking.

SAG₃₂ is a distance in parallel with the optical axis from the maximumeffective diameter position on the image-side surface of the third lenselement to an on-axis vertex on the image-side surface of the third lenselement and CT₃ is the central thickness of the third lens element. Whenthe relation of 1.2<|SAG₃₂|/CT₃<1.5 is satisfied, the angle of incidenceonto the image sensor from the off-axis field is reduced and theoff-axis aberration is corrected.

R₇ is a curvature radius of the object-side surface of the fourth lenselement; and R₈ is a curvature radius of the image-side surface of thefourth lens element. When the fourth lens element satisfies0.75<(R₇+R₈)/(R₇−R₈)<1.0, the lens shape of the fourth lens element ismaintained, which is favorable for correcting the high order aberrationgenerated by the optical lens assembly for image taking.

f is a focal length of the optical lens assembly for image taking; f₁ isa focal length of the first lens element; f₂ is a focal length of thesecond lens element; f₃ is a focal length of the third lens element; andf₄ is a focal length of the fourth lens element. When the relation of0.7<(f/f₁)+(f/f₂)+(f/f₃)+(f/f₄)<1.0 is satisfied, the arrangement of thefirst lens element, the second lens element, the third lens element andthe fourth lens element is much more proper, thereby it is favorable forreducing the sensitivity and the aberration of the optical lens assemblyfor image taking.

f₁ is the focal length of the first lens element; f₂ is the focal lengthof the second lens element. When the first lens element and the secondlens element satisfy −0.6<f₁/f₂<−0.2, it is favorable for correcting theaberration to enhance the image quality.

CT₂ is a central thickness of the second lens element. When the secondlens element satisfies 0.10 millimeters (mm)<CT₂<0.25 mm, it isfavorable for reducing the complexity of manufacturing the second lenselement while keeping the optical lens assembly compact.

In the optical lens assembly for image taking according to thedisclosure, the materials of the lens elements may be plastic or glass.When the material of the lens element is plastic, the manufacturing costmay be effectively reduced. Otherwise, when the material of the lenselement is glass, the freedom for distributing the refractive power ofthe optical lens assembly for image taking is increased. Moreover, thesurface shape of the lens elements can be easily made into non-sphericalprofiles, allowing more design parameter freedom which can be used toreduce the aberrations and the total number of the lens elements used inan optical lens assembly. Consequently, the total track length of theoptical lens assembly for image taking may be shortened effectively.

In addition, each object-side surface and each image-side surface ofevery lens element has a paraxial region and a peripheral region. Theparaxial region refers to the region of the surface where rays travelclose to or near the optical axis and the peripheral region refers tothe region of the surface where rays travel away from the optical axis.Particularly, a convex surface means the surface at a paraxial region isconvex; a concave surface means the surface at a paraxial region isconcave.

In the present optical lens assembly for image taking, there can be atleast one stop provided, such as an aperture stop, a glare stop or afield stop. Said glare stop or said field stop is used for eliminatingthe stray light and thereby improving the image resolution thereof.

In the present optical lens assembly for image taking, the aperture stopcan be configured as a front stop or a middle stop. A front stop canprovide a longer distance between an exit pupil of the system and animage plane and which improves the image-sensing efficiency of an imagesensor of CCD or CMOS. A middle stop is favorable for expanding thefield of view of the assembly and thereby provides a wider field of viewfor the same.

As for the optical lens assembly for image taking, the specific schemesare further described with the following embodiments. Parameters in theembodiments are defined as follows. The aspheric surface in theembodiments may be represented by, but not limited to, the followingaspheric surface equation (Formula ASP):

${X(Y)} = {{\left( {Y^{2}/R} \right)/\left( {1 + {{sqrt}\left( {1 - {\left( {1 + k} \right)*\left( {Y/R} \right)^{2}}} \right)}} \right)} + {\sum\limits_{i}{({Ai})*\left( Y^{i} \right)}}}$

wherein X is the relative distance between a point on the asphericsurface at a distance Y from the optical axis and the tangential planeat the aspheric surface vertex, Y is the distance from the point on thecurve of the aspheric surface to the optical axis, k is a conic factor,Ai is an i^(th) order aspheric surface coefficient, R is the curvatureradius, and in the embodiments, i may be, but is not limited to, 4, 6,8, 10, 12, 14 and 16.

The First Embodiment (Embodiment 1)

Referring to FIGS. 1A to 1D, the optical lens assembly for image taking1 of the first embodiment comprises, from an object side to an imageside along an optical axis (from left to right in FIG. 1A) in sequence,a first lens element 110, an aperture stop 100, a second lens element120, a third lens element 130, a fourth lens element 140, an IR-cutfilter (infrared-cut filter) 150 and an image plane 160 including animage sensor 170.

The first lens element 110 made of plastic with positive refractivepower having a convex object-side surface 111 at a paraxial region, aconvex image-side surface 112 at a paraxial region, and the object-sideand image-side surfaces 111 and 112 thereof being aspheric. The secondlens element 120 made of plastic with negative refractive power havingan object-side surface 121 being concave at a paraxial region and convexat a peripheral region, a concave image-side surface 122 at a paraxialregion, and the object-side and image-side surfaces 121 and 122 thereofbeing aspheric. The third lens element 130 made of plastic with positiverefractive power having a concave object-side surface 131 at a paraxialregion, a convex image-side surface 132 at a paraxial region, and theobject-side and image-side surfaces 131 and 132 thereof being aspheric.The fourth lens element 140 made of plastic with negative refractivepower having a concave object-side surface 141 at a paraxial region, animage-side surface 142 being concave at a paraxial region and convex ata peripheral region, and the object-side and image-side surfaces 141 and142 thereof being aspheric.

In this embodiment, the reference wavelength of the incident light rayon the optical lens assembly for image taking 1 is 587.6 nm. However,the reference wavelength of the light does not intend to limit thedisclosure. In some embodiments, light with different wavelength can beutilized for demonstrations of different purposes.

The detailed data of the optical lens assembly for image taking 1 is asshown in Table 1-1 below:

TABLE 1-1 Embodiment 1 f = 4.58 mm, Fno = 2.85, HFOV = 31.7 deg.Curvature Focal Surface radius Thickness length # (mm) (mm) MaterialIndex Abbe # (mm) 0 Object — Plano Infinity — — — — 1 Lens 1 1.467 ASP0.605 Plastic 1.544 55.9 2.63 2 −50.000 ASP −0.007 3 Ape. Stop — Plano0.075 — — — — 4 Lens 2 −27.502 ASP 0.316 Plastic 1.632 23.4 −4.71 53.354 ASP 1.009 6 Lens 3 −1.371 ASP 0.666 Plastic 1.544 55.9 2.70 7−0.830 ASP 0.218 8 Lens 4 −21.009 ASP 0.400 Plastic 1.530 55.8 −2.70 91.545 ASP 0.800 10 IR-cut filter — Plano 0.200 Glass 1.517 64.2 — 11 —Plano 0.740 12 Image Plane — Plano — — — — — Note: Reference wavelengthis d-line 587.6 nm, and ASP represents aspheric.

In Table 1-1, from the object-side surface 111 to the image-side surface142, all the surfaces can be aspheric, and the aspheric surfaces cansatisfy Formula ASP, but are not limited thereto. As for the parametersof the aspheric surfaces, reference is made to Table 1-2 below:

TABLE 1-2 Aspheric Coefficients Surface# 1 2 4 5 k = −3.7088E−011.0000E+01 −1.0000E+01 5.0000E+00 A4 =  3.7722E−03 −8.9123E−02 −1.7312E−02 7.4259E−02 A6 = −7.9788E−03 7.9461E−02  6.4881E−023.8014E−02 A8 = −6.7303E−03 −6.6730E−02   1.8385E−01 5.5458E−02 A10 =−3.1265E−02 2.8203E−02 −3.8755E−01 — A12 = — —  3.0251E−01 — Surface# 67 8 9 k = −2.9495E−01 −3.0402E+00 −2.0000E+01 −1.4244E+01 A4 =−1.0615E−01 −2.2064E−01 −3.9648E−02 −8.1878E−02 A6 = −1.0745E−01 9.2379E−02  1.9040E−02  3.7147E−02 A8 =  9.3646E−02 −5.6822E−02−2.8517E−03 −1.3669E−02 A10 = −3.3949E−01 −8.5423E−03 −4.6362E−04 2.6317E−03 A12 =  6.5307E−01  2.4266E−02 −5.0089E−07 −1.0546E−04 A14 =−5.1217E−01  5.0379E−03  6.9454E−05 −5.2988E−05 A16 =  1.4300E−01−4.8686E−03 −9.3417E−06  7.0521E−06

In Table 1-1, the curvature radius, the thickness and the focal lengthare shown in millimeters (mm). Surface numbers 0-12 represent thesurfaces sequentially arranged from the object-side to the image-sidealong the optical axis. “f” stands for the focal length, “Fno” is thef-number, and “HFOV” is a half of maximal field of view of thisembodiment. In Table 1-2, k represents the conic coefficient of theequation of the aspheric surface profiles. A1-A16 represent the asphericcoefficients ranging from the 1^(st) order to the 16^(th) order. Alllabels for Tables of the remaining embodiments share the samedefinitions as those in Table 1-1 and Table 1-2 of the first embodiment,and their definitions will not be stated again.

The content of Table 1-3 may be deduced from Table 1-1:

TABLE 1-3 Embodiment 1 f (mm) 4.58 (R₇ + R₈)/(R₇ − R₈) 0.86 Fno 2.85Dsr₄/Dr₁r₄ 0.40 HFOV(deg.) 31.7 Dr₁r₄/T₂₃ 0.98 V₁/V₂ 2.39 |SAG₃₂|/CT₃1.30 CT₂ (mm) 0.316 f₁/f₂ −0.558 T₂₃/CT₃ 1.515 f/f₁ + f/f₂ + f/f₃ + f/f₄0.772 R₁/R₂ −0.03 — —

The Second Embodiment (Embodiment 2)

Referring to FIGS. 2A to 2D, the optical lens assembly for image taking2 of the second embodiment comprises, from an object side to an imageside along an optical axis in sequence, a first lens element 210, anaperture stop 200, a second lens element 220, a third lens element 230,a fourth lens element 240, an IR-cut filter 250 and an image plane 260including an image sensor 270.

The first lens element 210 made of plastic with positive refractivepower having a convex object-side surface 211 at a paraxial region, aconcave image-side surface 212 at a paraxial region, and the object-sideand image-side surfaces 211 and 212 thereof being aspheric. The secondlens element 220 made of plastic with negative refractive power havingan object-side surface 221 being concave at a paraxial region and convexat a peripheral region, a concave image-side surface 222 at a paraxialregion, and the object-side and image-side surfaces 221 and 222 thereofbeing aspheric. The third lens element 230 made of plastic with positiverefractive power having a concave object-side surface 231 at a paraxialregion, a convex image-side surface 232 at a paraxial region, and theobject-side and image-side surfaces 231 and 232 thereof being aspheric.The fourth lens element 240 made of plastic with negative refractivepower having a concave object-side surface 241 at a paraxial region, animage-side surface 242 being concave at a paraxial region and convex ata peripheral region, and the object-side and image-side surfaces 241 and242 thereof being aspheric.

The detailed data of the optical lens assembly for image taking 2 is asshown in Table 2-1 below:

TABLE 2-1 Embodiment 2 f = 4.22 mm, Fno = 2.60, HFOV = 33.7 deg.Curvature Focal Surface radius Thickness length # (mm) (mm) MaterialIndex Abbe # (mm) 0 Object — Plano Infinity — — — — 1 Lens 1 1.401 ASP0.538 Plastic 1.544 55.9 2.83 2 13.333 ASP 0.010 3 Ape. Stop — Plano0.063 — — — — 4 Lens 2 −21.882 ASP 0.240 Plastic 1.640 23.3 −6.59 55.240 ASP 0.937 6 Lens 3 −1.430 ASP 0.558 Plastic 1.544 55.9 3.29 7−0.904 ASP 0.030 8 Lens 4 −96.154 ASP 0.802 Plastic 1.544 55.9 −3.17 91.764 ASP 0.800 10 IR-cut filter — Plano 0.300 Glass 1.517 64.2 — 11 —Plano 0.574 12 Image Plane — Plano — — — — — Note: Reference wavelengthis d-line 587.6 nm, and ASP represents aspheric.

As for the parameters of the aspheric surfaces, reference is made toTable 2-2 below.

TABLE 2-2 Aspheric Coefficients Surface# 1 2 4 5 k = −2.7718E−01−1.0000E+01 0.0000E+00 −2.7273E+00 A4 = −3.5277E−03 −1.2189E−019.1623E−03  1.5670E−01 A6 =  2.8440E−02  9.4036E−02 1.8989E−01 2.0134E−01 A8 = −1.5325E−01 −5.9171E−02 −1.1625E−01  −2.8523E−01 A10 = 2.0241E−01 −1.1397E−01 −1.3306E−01   3.5630E−01 A12 = −1.8569E−01 7.0950E−02 2.0031E−01 −1.2371E−01 Surface# 6 7 8 9 k = −8.3075E−01−2.8208E+00  3.0000E+00 −1.2857E+01 A4 = −4.0871E−02 −1.7798E−01−8.2639E−02 −7.2268E−02 A6 = −1.5752E−01  5.3502E−02  3.4985E−02 2.6211E−02 A8 =  3.3238E−01 −1.0268E−02 −5.3215E−03 −8.5113E−03 A10 =−4.7573E−01  1.6074E−02 −2.0649E−03  1.4520E−03 A12 =  5.5703E−01 3.1868E−03 −3.6888E−05 −8.9987E−05 A14 = −3.7006E−01 −4.2106E−03 2.0264E−04 −1.2586E−05 A16 =  1.0149E−01  5.2861E−04 −7.3636E−06 1.5215E−06

The content of Table 2-3 may be deduced from Table 2-1.

TABLE 2-3 Embodiment 2 f (mm) 4.22 (R₇ + R₈)/(R₇ − R₈) 0.96 Fno 2.60Dsr₄/Dr₁r₄ 0.36 HFOV(deg.) 33.7 Dr₁r₄/T₂₃ 0.91 V₁/V₂ 2.40 |SAG₃₂|/CT₃1.26 CT₂ (mm) 0.240 f₁/f₂ −0.430 T₂₃/CT₃ 1.679 f/f₁ + f/f₂ + f/f₃ + f/f₄0.802 R₁/R₂ 0.11 — —

The Third Embodiment (Embodiment 3)

Referring to FIGS. 3A to 3D, the optical lens assembly for image taking3 of the third embodiment comprises, from an object side to an imageside along an optical axis in sequence, an aperture stop 300, a firstlens element 310, a second lens element 320, a third lens element 330, afourth lens element 340, an IR-cut filter 350 and an image plane 360including an image sensor 370.

The first lens element 310 made of plastic with positive refractivepower having a convex object-side surface 311 at a paraxial region, aconvex image-side surface 312 at a paraxial region, and the object-sideand image-side surfaces 311 and 312 thereof being aspheric. The secondlens element 320 made of plastic with negative refractive power havingan object-side surface 321 being concave at a paraxial region and convexat a peripheral region, a concave image-side surface 322 at a paraxialregion, and the object-side and image-side surfaces 321 and 322 thereofbeing aspheric. The third lens element 330 made of plastic with positiverefractive power having a concave object-side surface 331 at a paraxialregion, a convex image-side surface 332 at a paraxial region, and theobject-side and image-side surfaces 331 and 332 thereof being aspheric.The fourth lens element 340 made of plastic with negative refractivepower having a concave object-side surface 341 at a paraxial region, animage-side surface 342 being concave at a paraxial region and convex ata peripheral region, and the object-side and image-side surfaces 341 and342 thereof being aspheric.

The detailed data of the optical lens assembly for image taking 3 is asshown in Table 3-1 below.

TABLE 3-1 Embodiment 3 f = 3.16 mm, Fno = 2.50, HFOV = 37.2 deg.Curvature Focal Surface radius Thickness length # (mm) (mm) MaterialIndex Abbe # (mm) 0 Object — Plano Infinity — — — — 1 Ape. Stop — Plano−0.124 — — — 2 Lens 1 1.398 ASP 0.437 Plastic 1.544 55.9 2.41 3 −18.784ASP 0.106 4 Lens 2 −4.907 ASP 0.230 Plastic 1.634 23.8 −5.10 5 9.668 ASP0.725 6 Lens 3 −2.301 ASP 0.448 Plastic 1.544 55.9 2.29 7 −0.864 ASP0.050 8 Lens 4 −92.625 ASP 0.775 Plastic 1.544 55.9 −2.04 9 1.125 ASP0.500 10 IR-cut filter — Plano 0.200 Glass 1.517 64.2 — 11 — Plano 0.40412 Image Plane — Plano — — — — — Note: Reference wavelength is d-line587.6 nm, and ASP represents aspheric.

As for the parameters of the aspheric surfaces, reference is made toTable 3-2 below.

TABLE 3-2 Aspheric Coefficients Surface# 2 3 4 5 k = −3.1348E−01−1.0000E+01 8.0573E−01 −9.4103E−01 A4 = −2.6398E−03 −3.3758E−031.2856E−01  1.8792E−01 A6 =  7.1184E−02 −1.6505E−01 −2.9274E−01 −1.5053E−01 A8 = −3.9064E−01 −5.3144E−01 −5.9578E−01  −3.2201E−01 A10 = 7.1001E−01  4.8907E−01 1.2917E+00  9.8931E−01 A12 = −1.2552E+00−8.9056E−02 4.1486E−02 −4.0552E−01 Surface# 6 7 8 9 k = −3.8312E+00−3.9375E+00 −1.0000E+01 −7.8287E+00 A4 =  4.3031E−02 −1.8316E−01−1.1156E−01 −1.0225E−01 A6 = −1.3068E−01  2.8895E−01  7.7127E−02 5.3651E−02 A8 =  9.3787E−01 −4.5535E−02 −1.0326E−02 −2.2803E−02 A10 =−2.4594E+00  8.9727E−03 −6.9155E−03  4.9977E−03 A12 =  3.1468E+00−2.4744E−02 −2.2103E−04 −3.8027E−04 A14 = −1.9753E+00 −5.5294E−02 1.2223E−03 −6.7563E−05 A16 =  3.9906E−01  3.5069E−02 −1.8080E−04 1.1080E−05

The content of Table 3-3 may be deduced from Table 3-1.

TABLE 3-3 Embodiment 3 f (mm) 3.16 (R₇ + R₈)/(R₇ − R₈) 0.98 Fno 2.50Dsr₄/Dr₁r₄ 0.84 HFOV(deg.) 37.2 Dr₁r₄/T₂₃ 1.07 V₁/V₂ 2.35 |SAG₃₂|/CT₃0.88 CT₂ (mm) 0.230 f₁/f₂ −0.472 T₂₃/CT₃ 1.618 f/f₁ + f/f₂ + f/f₃ + f/f₄0.521 R₁/R₂ −0.07 — —

The Fourth Embodiment (Embodiment 4)

Referring to FIGS. 4A to 4D, the optical lens assembly for image taking4 of the fourth embodiment comprises, from an object side to an imageside along an optical axis in sequence, a first lens element 410, anaperture stop 400, a second lens element 420, a third lens element 430,a fourth lens element 440, an IR-cut filter 450 and an image plane 460including an image sensor 470.

The first lens element 410 made of plastic with positive refractivepower having a convex object-side surface 411 at a paraxial region, aconcave image-side surface 412 at a paraxial region, and the object-sideand image-side surfaces 411 and 412 thereof being aspheric. The secondlens element 420 made of plastic with negative refractive power havingan object-side surface 421 being concave at a paraxial region and convexat a peripheral region, a concave image-side surface 422 at a paraxialregion, and the object-side and image-side surfaces 421 and 422 thereofbeing aspheric. The third lens element 430 made of plastic with positiverefractive power having a concave object-side surface 431 at a paraxialregion, a convex image-side surface 432 at a paraxial region, and theobject-side and image-side surfaces 431 and 432 thereof being aspheric.The fourth lens element 440 made of plastic with negative refractivepower having a concave object-side surface 441 at a paraxial region, animage-side surface 442 being concave at a paraxial region and convex ata peripheral region, and the object-side and image-side surfaces 441 and442 thereof being aspheric.

The detailed data of the optical lens assembly for image taking 4 is asshown in Table 4-1 below.

TABLE 4-1 Embodiment 4 f = 4.24 mm, Fno = 2.40, HFOV = 33.6 deg.Curvature Focal Surface radius Thickness length # (mm) (mm) MaterialIndex Abbe # (mm) 0 Object — Plano Infinity — — — — 1 Lens 1 1.477 ASP0.564 Plastic 1.544 55.9 3.02 2 12.628 ASP −0.025 3 Ape. Stop — Plano0.101 — — — — 4 Lens 2 −16.191 ASP 0.230 Plastic 1.650 21.4 −9.27 59.639 ASP 0.887 6 Lens 3 −1.278 ASP 0.503 Plastic 1.544 55.9 3.98 7−0.915 ASP 0.050 8 Lens 4 −16.008 ASP 0.996 Plastic 1.535 56.3 −3.51 92.174 ASP 0.800 10 IR-cut filter — Plano 0.300 Glass 1.517 64.2 — 11 —Plano 0.499 12 Image Plane — Plano — — — — — Note: Reference wavelengthis d-line 587.6 nm, and ASP represents aspheric.

As for the parameters of the aspheric surfaces, reference is made toTable 4-2 below.

TABLE 4-2 Aspheric Coefficients Surface# 1 2 4 5 k = −3.9600E−01−1.0000E+00 −1.0000E+00 −1.0000E+01  A4 = −1.0349E−03 −1.5629E−01−1.2051E−02 1.4376E−01 A6 = −3.3372E−02  6.1381E−02  2.4071E−012.2513E−01 A8 =  2.9815E−02  1.4497E−04 −1.7614E−01 −2.0940E−01  A10 =−1.1699E−01 −8.2061E−02  8.5465E−02 1.6181E−01 A12 =  1.6869E−02 3.4773E−02  1.7518E−02 1.1102E−02 Surface# 6 7 8 9 k = −1.2732E+00−2.4919E+00  0.0000E+00 −1.4828E+01 A4 = −5.4571E−02 −1.3836E−01−3.6118E−02 −5.8863E−02 A6 = −1.4167E−01  3.2188E−02  8.9260E−03 2.1901E−02 A8 =  4.3308E−01  2.9626E−02 −2.7124E−04 −7.648 1E−03  A10 =−5.1869E−01  2.2476E−02 −1.7875E−03  1.4801E−03 A12 =  5.0188E−01−8.8402E−03 −2.0505E−04 −1.4250E−04 A14 = −3.4547E−01 −1.0509E−02 2.1570E−04 −7.5030E−07 A16 =  1.0990E−01  4.6847E−03  2.5326E−06 7.7316E−07

The content of Table 4-3 may be deduced from Table 4-1.

TABLE 4-3 Embodiment 4 f (mm) 4.24 (R₇ + R₈)/(R₇ − R₈) 0.76 Fno 2.40Dsr₄/Dr₁r₄ 0.38 HFOV(deg.) 33.6 Dr₁r₄/T₂₃ 0.98 V₁/V₂ 2.61 |SAG₃₂|/CT₃1.19 CT₂ (mm) 0.230 f₁/f₂ −0.326 T₂₃/CT₃ 1.763 f/f₁ + f/f₂ + f/f₃ + f/f₄0.804 R₁/R₂ 0.12 — —

The Fifth Embodiment (Embodiment 5)

Referring to FIGS. 5A to 5D, the optical lens assembly for image taking5 of the fifth embodiment comprises, from an object side to an imageside along an optical axis in sequence, a first lens element 510, anaperture stop 500, a second lens element 520, a third lens element 530,a fourth lens element 540, an IR-cut filter 550 and an image plane 560including an image sensor 570.

The first lens element 510 made of plastic with positive refractivepower having a convex object-side surface 511 at a paraxial region, aconcave image-side surface 512 at a paraxial region, and the object-sideand image-side surfaces 511 and 512 thereof being aspheric. The secondlens element 520 made of plastic with negative refractive power havingan object-side surface 521 being concave at a paraxial region and convexat a peripheral region, a concave image-side surface 522 at a paraxialregion, and the object-side and image-side surfaces 521 and 522 thereofbeing aspheric. The third lens element 530 made of plastic with positiverefractive power having a concave object-side surface 531 at a paraxialregion, a convex image-side surface 532 at a paraxial region, and theobject-side and image-side surfaces 531 and 532 thereof being aspheric.The fourth lens element 540 made of plastic with negative refractivepower having a concave object-side surface 541 at a paraxial region, animage-side surface 542 being concave at a paraxial region and convex ata peripheral region, and the object-side and image-side surfaces 541 and542 thereof being aspheric.

The detailed data of the optical lens assembly for image taking 5 is asshown in Table 5-1 below.

Table 5-1 Embodiment 5 f = 4.21 mm, Fno = 2.60, HFOV = 33.8 deg.Curvature Focal Surface Radius Thickness length # (mm) (mm) MaterialIndex Abbe # (mm) 0 Object — Plano Infinity — — — — 1 Lens 1 1.396 ASP0.541 Plastic 1.544 55.9 2.83 2 12.987 ASP 0.012 3 Ape. Stop — Plano0.054 — — — — 4 Lens 2 −21.882 ASP 0.240 Plastic 1.640 23.3 −6.81 55.468 ASP 0.982 6 Lens 3 −1.327 ASP 0.488 Plastic 1.544 55.9 4.08 7−0.938 ASP 0.030 8 Lens 4 −96.154 ASP 0.983 Plastic 1.544 55.9 −3.68 92.053 ASP 0.800 10 IR-cut filter — Plano 0.300 Glass 1.517 64.2 — 11 —Plano 0.423 12 Image Plane — Plano — — — — — Note: Reference wavelengthis d-line 587.6 nm, and ASP represents aspheric.

As for the parameters of the aspheric surfaces, reference is made toTable 5-2 below.

TABLE 5-2 Aspheric Coefficients Surface# 1 2 4 5 k = −2.1472E−01 1.3365E+01  2.0000E+01 −5.0570E+00 A4 = −7.0134E−03 −1.3245E−01−2.7741E−03  1.5294E−01 A6 =  3.3523E−02  1.2273E−01  2.2929E−01 2.1296E−01 A8 = −1.6331E−01 −7.5352E−02 −1.8507E−01 −3.3739E−01 A10 = 2.1611E−01 −1.2271E−01 −6.3417E−02  4.2148E−01 A12 = −1.8981E−01 8.0174E−02  1.6503E−01 −1.5564E−01 Surface# 6 7 8 9 k = −8.0936E−01−2.5573E+00 −2.0000E+01 −1.3381E+01 A4 = −4.1480E−02 −1.6444E−01−6.4761E−02 −5.6728E−02 A6 = −1.8101E−01  3.2789E−02  2.9318E−02 1.8387E−02 A8 =  3.9674E−01 −3.5037E−03 −4.6741E−03 −5.8367E−03 A10 =−5.4309E−01  3.5609E−02 −1.9021E−03  1.0848E−03 A12 =  5.5613E−01 1.4681E−04  1.6523E−04 −1.1383E−04 A14 = −3.0714E−01 −1.7004E−02 1.1377E−04  2.3914E−06 A16 =  4.9077E−02  4.6559E−03 −1.1852E−05 2.1022E−07

The content of Table 5-3 may be deduced from Table 5-1.

TABLE 5-3 Embodiment 5 f (mm) 4.21 (R₇ + R₈)/(R₇ − R₈) 0.96 Fno 2.60Dsr₄/Dr₁r₄ 0.35 HFOV(deg.) 33.8 Dr₁r₄/T₂₃ 0.86 V₁/V₂ 2.40 |SAG₃₂|/CT₃1.44 CT₂ (mm) 0.240 f₁/f₂ −0.415 T₂₃/CT₃ 2.012 f/f₁ + f/f₂ + f/f₃ + f/f₄0.760 R₁/R₂ 0.11 — —

The Sixth Embodiment (Embodiment 6)

Referring to FIGS. 6A to 6D, the optical lens assembly for image taking6 of the sixth embodiment comprises, from an object side to an imageside along an optical axis in sequence, a first lens element 610, anaperture stop 600, a second lens element 620, a third lens element 630,a fourth lens element 640, an IR-cut filter 650 and an image plane 660including an image sensor 670.

The first lens element 610 made of plastic with positive refractivepower having a convex object-side surface 611 at a paraxial region, aconcave image-side surface 612 at a paraxial region, and the object-sideand image-side surfaces 611 and 612 thereof being aspheric. The secondlens element 620 made of plastic with negative refractive power havingan object-side surface 621 being concave at a paraxial region and convexat a peripheral region, a concave image-side surface 622 at a paraxialregion, and the object-side and image-side surfaces 621 and 622 thereofbeing aspheric. The third lens element 630 made of plastic with positiverefractive power having a concave object-side surface 631 at a paraxialregion, a convex image-side surface 632 at a paraxial region, and theobject-side and image-side surfaces 631 and 632 thereof being aspheric.The fourth lens element 640 made of plastic with negative refractivepower having a concave object-side surface 641 at a paraxial region, animage-side surface 642 being concave at a paraxial region and convex ata peripheral region, and the object-side and image-side surfaces 641 and642 thereof being aspheric.

The detailed data of the optical lens assembly for image taking 6 is asshown in Table 6-1 below.

TABLE 6-1 Embodiment 6 f = 4.25 mm, Fno = 2.60, HFOV = 33.6 deg.Curvature Focal Surface Radius Thickness length # (mm) (mm) MaterialIndex Abbe # (mm) 0 Object — Plano Infinity — — — — 1 Lens 1 1.382 ASP0.551 Plastic 1.544 55.9 2.80 2 12.987 ASP 0.011 3 Ape. Stop — Plano0.048 — — — — 4 Lens 2 −21.882 ASP 0.240 Plastic 1.640 23.3 −6.93 55.583 ASP 0.973 6 Lens 3 −1.196 ASP 0.428 Plastic 1.544 55.9 5.04 7−0.938 ASP 0.030 8 Lens 4 −118.906 ASP 1.072 Plastic 1.544 55.9 −4.28 92.381 ASP 0.800 10 IR-cut filter — Plano 0.300 Glass 1.517 64.2 — 11 —Plano 0.401 12 Image Plane — Plano — — — — — Note: Reference wavelengthis d-line 587.6 nm, and ASP represents aspheric.

As for the parameters of the aspheric surfaces, reference is made toTable 6-2 below.

TABLE 6-2 Aspheric Coefficients Surface# 1 2 4 5 k = −1.9776E−01−2.0000E+01  2.0000E+01 −6.9385E+00 A4 = −6.3982E−03 −1.3692E−01−1.0716E−02  1.5136E−01 A6 =  3.3612E−02  1.4112E−01  2.4027E−01 2.0873E−01 A8 = −1.5938E−01 −9.0475E−02 −1.9312E−01 −3.3568E−01 A10 = 2.1378E−01 −1.0933E−01 −5.1506E−02  4.2625E−01 A12 = −1.8695E−01 7.2423E−02  1.5526E−01 −1.5508E−01 Surface# 6 7 8 9 k = −9.1034E−01−2.5635E+00 −2.0000E+01 −1.5988E+01 A4 = −3.4900E−02 −1.6160E−01−4.7728E−02 −5.3787E−02 A6 = −1.4704E−01  5.2202E−02  2.0242E−02 1.7478E−02 A8 =  4.3643E−01  2.1599E−02 −4.0349E−03 −5.7351E−03 A10 =−5.8370E−01  3.8296E−02 −1.1713E−03  1.0845E−03 A12 =  5.4398E−01−1.2525E−02  1.2895E−04 −1.2011E−04 A14 = −2.9231E−01 −2.5665E−02 3.6585E−05  4.7827E−06 A16 =  3.3752E−02  1.0648E−02  2.6279E−06−6.6075E−08

The content of Table 6-3 may be deduced from Table 6-1.

TABLE 6-3 Embodiment 6 f (mm) 4.25 (R₇ + R₈)/(R₇ − R₈) 0.96 Fno 2.60Dsr₄/Dr₁r₄ 0.34 HFOV(deg.) 33.6 Dr₁r₄/T₂₃ 0.87 V₁/V₂ 2.40 |SAG₃₂|/CT₃1.44 CT₂ (mm) 0.240 f₁/f₂ −0.403 T₂₃/CT₃ 2.273 f/f₁ + f/f₂ + f/f₃ + f/f₄0.756 R₁/R₂ 0.11 — —

The Seventh Embodiment (Embodiment 7)

Referring to FIGS. 7A to 7D, the optical lens assembly for image taking7 of the seventh embodiment comprises, from an object side to an imageside along an optical axis in sequence, an aperture stop 700, a firstlens element 710, a second lens element 720, a third lens element 730, afourth lens element 740, an IR-cut filter 750 and an image plane 760including an image sensor 770.

The first lens element 710 made of plastic with positive refractivepower having a convex object-side surface 711 at a paraxial region, aconvex image-side surface 712 at a paraxial region, and the object-sideand image-side surfaces 711 and 712 thereof being aspheric. The secondlens element 720 made of plastic with negative refractive power havingan object-side surface 721 being concave at a paraxial region and convexat a peripheral region, a concave image-side surface 722 at a paraxialregion, and the object-side and image-side surfaces 721 and 722 thereofbeing aspheric. The third lens element 730 made of plastic with positiverefractive power having a concave object-side surface 731 at a paraxialregion, a convex image-side surface 732 at a paraxial region, and theobject-side and image-side surfaces 731 and 732 thereof being aspheric.The fourth lens element 740 made of plastic with negative refractivepower having a concave object-side surface 741 at a paraxial region, animage-side surface 742 being concave at a paraxial region and convex ata peripheral region, and the object-side and image-side surfaces 741 and742 thereof being aspheric.

The detailed data of the optical lens assembly for image taking 7 is asshown in Table 7-1 below.

TABLE 7-1 Embodiment 7 f = 3.15 mm, Fno = 2.75, HFOV = 37.2 deg.Curvature Focal Surface radius Thickness length # (mm) (mm) MaterialIndex Abbe # (mm) 0 Object — Plano Infinity — — — — 1 Ape. Stop — Plano−0.111 — — — 2 Lens 1 1.318 ASP 0.398 Plastic 1.544 55.9 2.37 3 −49.378ASP 0.100 4 Lens 2 −4.695 ASP 0.230 Plastic 1.634 23.8 −4.79 5 8.754 ASP0.711 6 Lens 3 −2.349 ASP 0.473 Plastic 1.544 55.9 1.98 7 −0.792 ASP0.050 8 Lens 4 −92.593 ASP 0.652 Plastic 1.544 55.9 −1.82 9 1.001 ASP0.500 10 IR-cut filter — Plano 0.200 Glass 1.517 64.2 — 11 — Plano 0.49012 Image Plane — Plano — — — — — Note: Reference wavelength is d-line587.6 nm, and ASP represents aspheric.

As for the parameters of the aspheric surfaces, reference is made toTable 7-2 below.

TABLE 7-3 Aspheric Coefficients Surface# 2 3 4 5 k = −3.2979E−02−2.0000E+01 1.0362E+01 −1.8693E+01 A4 =  1.1036E−02  2.9501E−031.4679E−01  2.1132E−01 A6 = −4.1949E−02 −1.7838E−01 −4.1033E−01 −1.9723E−01 A8 =  1.5892E−01 −5.1364E−01 −3.6671E−01  −2.215 1E−01  A10= −2.9867E−01  1.5730E−01 1.0063E+00  1.0492E+00 A12 = −1.0314E+00 2.5800E−01 5.9282E−01 −3.5248E−01 Surface# 6 7 8 9 k = −3.2777E+00−3.8478E+00 −2.0000E+01 −7.8096E+00 A4 =  2.4866E−02 −2.2406E−01−1.3951E−01 −1.1624E−01 A6 = −7.6117E−02  3.3347E−01  8.5993E−02 5.6522E−02 A8 =  8.8969E−01 −5.5267E−02 −8.3139E−03 −2.2867E−02 A10 =−2.4533E+00  5.1830E−03 −6.6480E−03  4.9853E−03 A12 =  3.1386E+00−2.5646E−02 −1.9395E−04 −3.7455E−04 A14 = −1.9612E+00 −5.4484E−02 1.1923E−03 −6.4601E−05 A16 =  3.9312E−01  3.6056E−02 −2.0899E−04 1.1277E−05

The content of Table 7-3 may be deduced from Table 7-1.

TABLE 7-3 Embodiment 7 f (mm) 3.15 (R₇ + R₈)/(R₇ − R₈) 0.98 Fno 2.75Dsr₄/Dr₁r₄ 0.85 HFOV(deg.) 37.2 Dr₁r₄/T₂₃ 1.02 V₁/V₂ 2.35 |SAG₃₂|/CT₃0.87 CT₂ (mm) 0.230 f₁/f₂ −0.494 T₂₃/CT₃ 1.503 f/f₁ + f/f₂ + f/f₃ + f/f₄0.527 R₁/R₂ −0.03 — —

The Eighth Embodiment (Embodiment 8)

Referring to FIGS. 8A to 8D, the optical lens assembly for image taking8 of the eighth embodiment comprises, from an object side to an imageside along an optical axis in sequence, an aperture stop 800, a firstlens element 810, a second lens element 820, a third lens element 830, afourth lens element 840, an IR-cut filter 850 and an image plane 860including an image sensor 870.

The first lens element 810 made of plastic with positive refractivepower having a convex object-side surface 811 at a paraxial region, aconcave image-side surface 812 at a paraxial region, and the object-sideand image-side surfaces 811 and 812 thereof being aspheric. The secondlens element 820 made of plastic with negative refractive power havingan object-side surface 821 being concave at a paraxial region and convexat a peripheral region, a concave image-side surface 822 at a paraxialregion, and the object-side and image-side surfaces 821 and 822 thereofbeing aspheric. The third lens element 830 made of plastic with positiverefractive power having a concave object-side surface 831 at a paraxialregion, a convex image-side surface 832 at a paraxial region, and theobject-side and image-side surfaces 831 and 832 thereof being aspheric.The fourth lens element 840 made of plastic with negative refractivepower having a concave object-side surface 841 at a paraxial region, animage-side surface 842 being concave at a paraxial region and convex ata peripheral region, and the object-side and image-side surfaces 841 and842 thereof being aspheric.

The detailed data of the optical lens assembly for image taking 8 is asshown in Table 8-1 below.

TABLE 8-1 Embodiment 8 f = 3.15 mm, Fno = 2.75, HFOV = 37.2 deg.Curvature Focal Surface radius Thickness length # (mm) (mm) MaterialIndex Abbe # (mm) 0 Object — Plano Infinity — — — — 1 Ape. Stop — Plano−0.111 — — — 2 Lens 1 1.309 ASP 0.398 Plastic 1.544 55.9 2.44 3 94.630ASP 0.100 4 Lens 2 −5.781 ASP 0.230 Plastic 1.634 23.8 −5.22 5 7.874 ASP0.717 6 Lens 3 −2.730 ASP 0.468 Plastic 1.544 55.9 1.95 7 −0.812 ASP0.056 8 Lens 4 −10.266 ASP 0.681 Plastic 1.544 55.9 −1.74 9 1.066 ASP0.500 10 IR-cut filter — Plano 0.200 Glass 1.517 64.2 — 11 — Plano 0.44712 Image Plane — Plano — — — — — Note: Reference wavelength is d-line587.6 nm, and ASP represents aspheric.

As for the parameters of the aspheric surfaces, reference is made toTable 8-2 below.

TABLE 8-2 Aspheric Coefficients Surface# 2 3 4 5 k =  1.0833E−01−5.0000E+01 2.1370E+01 −3.6528E+01 A4 = −6.3377E−03 −3.0138E−025.8259E−02  1.5834E−01 A6 =  2.1210E−02 −2.8995E−01 −3.8767E−01 −1.5233E−01 A8 = −9.8604E−02 −5.5070E−02 9.1195E−03 −8.1459E−02 A10 =−4.5524E−02 −3.7168E−01 5.4832E−01  8.8681E−01 A12 = −1.0314E+00 2.5800E−01 5.9282E−01 −3.5777E−01 Surface# 6 7 8 9 k = −1.1158E+00−4.0041E+00 −5.0000E+01 −8.1256E+00 A4 =  7.5304E−03 −2.3811E−01−1.1624E−01 −1.1034E−01 A6 = −4.2445E−02  3.7391E−01  8.5513E−02 5.5210E−02 A8 =  8.7419E−01 −6.9691E−02 −8.4977E−03 −2.2895E−02 A10 =−2.4890E+00 −1.6664E−03 −6.8785E−03  4.9934E−03 A12 =  3.1703E+00−2.6589E−02 −3.7576E−04 −3.4126E−04 A14 = −1.8983E+00 −5.2638E−02 1.1762E−03 −6.5678E−05 A16 =  3.1524E−01  3.5600E−02 −1.8478E−04 1.0265E−05

The content of Table 8-3 may be deduced from Table 8-1.

TABLE 8-3 Embodiment 8 f (mm) 3.15 (R₇ + R₈)/(R₇ − R₈) 0.81 Fno 2.75Dsr₄/Dr₁r₄ 0.85 HFOV(deg.) 37.2 Dr₁r₄/T₂₃ 1.02 V₁/V₂ 2.35 |SAG₃₂|/CT₃0.86 CT₂ (mm) 0.230 f₁/f₂ −0.466 T₂₃/CT₃ 1.532 f/f₁ + f/f₂ + f/f₃ + f/f₄0.489 R₁/R₂ 0.01 — —

It is to be noted that TABLES 1-8 show different data of the differentembodiments; however, the data of the different embodiments are obtainedfrom experiments. Therefore, any optical lens assembly of the samestructure is considered to be within the scope of the present disclosureeven if it uses different data. The embodiments depicted above and theappended drawings are exemplary and are not intended to limit the scopeof the present disclosure.

What is claimed is:
 1. An optical lens assembly for image taking comprising, in order from an object side to an image side: a first lens element with positive refractive power comprising a convex object-side surface at a paraxial region and an image-side surface; a second lens element with negative refractive power comprising a concave object-side surface at a paraxial region and an image-side surface; a third lens element with refractive power comprising a concave object-side surface at a paraxial region and a convex image-side surface at a paraxial region; and a fourth lens element made of plastic with negative refractive power comprising a concave object-side surface at a paraxial region and a concave image-side surface at a paraxial region wherein at least one of the object-side surface and the image-side surface is aspheric, and the image-side surface is convex at a peripheral region; wherein T₂₃ is an axial distance between the second lens element and the third lens element, CT₃ is a central thickness of the third lens element, R₁ is a curvature radius of the object-side surface of the first lens element, R₂ is a curvature radius of the image-side surface of the first lens element, Dr₁r₄ is an axial distance between the object-side surface of the first lens element and the image-side surface of the second lens element, and the optical lens assembly for image taking satisfies the following conditions: 1.45<T ₂₃ /CT ₃<3.0; −0.15<R ₁ /R ₂<0.50; and 0.70<Dr ₁ r ₄ /T ₂₃<1.08.
 2. The optical lens assembly for image taking according to claim 1, wherein the third lens element has positive refractive power.
 3. The optical lens assembly for image taking according to claim 2, wherein V₁ is an Abbe number of the first lens element, V₂ is an Abbe number of the second lens element, and the optical lens assembly for image taking satisfies the following condition: 1.8<V ₁ /V ₂<3.0.
 4. The optical lens assembly for image taking according to claim 3, further comprising: a stop disposed between the first lens element and the second lens element; wherein Dsr₄ is an axial distance between the stop and the image-side surface of the second lens element, Dr₁r₄ is the axial distance between the object-side surface of the first lens element and the image-side surface of the second lens element, and they satisfy the following condition: 0.30<Dsr ₄ /Dr ₁ r ₄<0.60.
 5. The optical lens assembly for image taking according to claim 3, wherein the object-side surface of the second lens element is convex at a peripheral region.
 6. The optical lens assembly for image taking according to claim 3, wherein SAG₃₂ is a distance in parallel with an optical axis from the maximum effective diameter position on the image-side surface of the third lens element to an on-axis vertex on the image-side surface of the third lens element, CT₃ is the central thickness of the third lens element, and the optical lens assembly for image taking satisfies the following condition: 1.2<|SAG ₃₂ |/CT ₃<1.5.
 7. The optical lens assembly for image taking according to claim 2, wherein T₂₃ is the axial distance between the second lens element and the third lens element, CT₃ is the central thickness of the third lens element and the optical lens assembly for image taking satisfies the following condition: 1.50≦T ₂₃ /CT ₃<2.05.
 8. The optical lens assembly for image taking according to claim 7, wherein T₂₃ is the axial distance between the second lens element and the third lens element, CT₃ is the central thickness of the third lens element, and the optical lens assembly for image taking satisfies the following condition: 1.50≦T ₂₃ /CT ₃<1.80.
 9. The optical lens assembly for image taking according to claim 7, wherein R₇ is a curvature radius of the object-side surface of the fourth lens element, R₈ is a curvature radius of the image-side surface of the fourth lens element and the optical lens assembly for image taking satisfies the following condition: 0.75<(R ₇ +R ₈)/(R ₇ −R ₈)<1.0.
 10. The optical lens assembly for image taking according to claim 7, wherein f is a focal length of the optical lens assembly for image taking, f₁ is a focal length of the first lens element, f₂ is a focal length of the second lens element, f₃ is a focal length of the third lens element, f₄ is a focal length of the fourth lens element, and the optical lens assembly for image taking satisfies the following condition: 0.7<(f/f ₁)+(f/f ₂)+(f/f ₃)+(f/f ₄)<1.0.
 11. The optical lens assembly for image taking according to claim 7, wherein f₁ is a focal length of the first lens element, f₂ is a focal length of the second lens element, and the optical lens assembly for image taking satisfies the following condition: −0.6<f ₁ /f ₂<−0.2.
 12. The optical lens assembly for image taking according to claim 7, wherein CT₂ is a central thickness of the second lens element and the optical lens assembly for image taking satisfies the following condition: 0.10 mm<CT ₂<0.25 mm.
 13. An optical lens assembly for image taking comprising, in order from an object side to an image side: a first lens element with positive refractive power comprising a convex object-side surface at a paraxial region and an image-side surface; a second lens element with negative refractive power comprising a concave object-side surface at a paraxial region and an image-side surface; a third lens element with refractive power comprising a concave object-side surface at a paraxial region and a convex image-side surface at a paraxial region; and a fourth lens element made of plastic with negative refractive power comprising a concave object-side surface at a paraxial region and a concave image-side surface at a paraxial region wherein at least one of the object-side surface and the image-side surface is aspheric, and the image-side surface is convex at a peripheral region; wherein the optical lens assembly for image taking further comprises a stop, T₂₃ is an axial distance between the second lens element and the third lens element, CT₃ is a central thickness of the third lens element, R₁ is a curvature radius of the object-side surface of the first lens element, R₂ is a curvature radius of the image-side surface of the first lens element, Dsr₄ is an axial distance between the stop and the image-side surface of the second lens element, Dr₁r₄ is an axial distance between the object-side surface of the first lens element and the image-side surface of the second lens element, and the optical lens assembly for image taking satisfies the following conditions: 1.50≦T ₂₃ /CT ₃<2.05; −0.33<R ₁ /R ₂<0.50; 0.30<Dsr ₄ /Dr ₁ r ₄<0.90.
 14. The optical lens assembly for image taking according to claim 13, wherein the third lens element has positive refractive power, and the image-side surface of the second lens element is concave at a paraxial region.
 15. The optical lens assembly for image taking according to claim 14, wherein T₂₃ is the axial distance between the second lens element and the third lens element, CT₃ is the central thickness of the third lens element, and the optical lens assembly for image taking satisfies the following condition: 1.50≦T ₂₃ /CT ₃<1.80.
 16. The optical lens assembly for image taking according to claim 15, wherein V₁ is an Abbe number of the first lens element, V₂ is an Abbe number of the second lens element, and the optical lens assembly for image taking satisfies the following condition: 1.8<V ₁ /V ₂<3.0.
 17. The optical lens assembly for image taking according to claim 15, wherein f₁ is a focal length of the first lens element, and f₂ is a focal length of the second lens element, and the optical lens assembly for image taking satisfies the following condition: −0.6<f ₁ /f ₂<−0.2.
 18. The optical lens assembly for image taking according to claim 15, wherein SAG₃₂ is a distance in parallel with an optical axis from the maximum effective diameter position on the image-side surface of the third lens element to an on-axis vertex on the image-side surface of the third lens element, CT₃ is the central thickness of the third lens element, and the optical lens assembly for image taking satisfies the following condition: 1.2<|SAG ₃₂ |/CT ₃<1.5.
 19. The optical lens assembly for image taking according to claim 14, wherein the stop is disposed between the first lens element and the second lens element, Dsr₄ is the axial distance between the stop and the image-side surface of the second lens element, Dr₁r₄ is the axial distance between the object-side surface of the first lens element and the image-side surface of the second lens element, and the optical lens assembly for image taking satisfies the following condition: 0.30<Dsr ₄ /Dr ₁ r ₄<0.60.
 20. The optical lens assembly for image taking according to claim 19, wherein R₇ is a curvature radius of the object-side surface of the fourth lens element, R₈ is a curvature radius of the image-side surface of the fourth lens element, and the optical lens assembly for image taking satisfies the following condition: 0.75<(R ₇ +R ₈)/(R ₇ −R ₈)<1.0.
 21. The optical lens assembly for image taking according to claim 19, wherein f is a focal length of the optical lens assembly for image taking, f₁ is a focal length of the first lens element, f₂ is a focal length of the second lens element, f₃ is a focal length of the third lens element, f₄ is a focal length of the fourth lens element, and the optical lens assembly for image taking satisfies the following condition: 0.7<(f/f ₁)+(f/f ₂)+(f/f ₃)+(f/f ₄)<1.0.
 22. The optical lens assembly for image taking according to claim 19, wherein R₁ is the curvature radius of the object-side surface of the first lens element, R₂ is the curvature radius of the image-side surface of the first lens element, and the optical lens assembly for image taking satisfies the following condition: −0.15<R ₁ /R ₂<0.50.
 23. The optical lens assembly for image taking according to claim 19, wherein CT₂ is a central thickness of the second lens element, and the optical lens assembly for image taking satisfies the following condition: 0.10 mm<CT ₂<0.25 mm. 